Bash-4.3 Official Patch 10

[Chet Ramey]

                             BASH PATCH REPORT
                             =================

Bash-Release:   4.3
Patch-ID:       bash43-010

Bug-Reported-by:        Albert Shih <Albert.Shih@obspm.fr>
Bug-Reference-ID:       Wed, 5 Mar 2014 23:01:40 +0100
Bug-Reference-URL:      
http://lists.gnu.org/archive/html/bug-bash/2014-03/msg00028.html

Bug-Description:

This patch changes the behavior of programmable completion to compensate
for two assumptions made by the bash-completion package.  Bash-4.3 changed
to dequote the argument to programmable completion only under certain
circumstances, to make the behavior of compgen more consistent when run
from the command line -- closer to the behavior when run by a shell function
run as part of programmable completion.  Bash-completion can pass quoted
arguments to compgen when the original word to be completed was not quoted,
expecting programmable completion to dequote the word before attempting
completion.

This patch fixes two cases:

1.  An empty string that bash-completion passes to compgen as a quoted null
    string ('').

2.  An unquoted word that bash-completion quotes using single quotes or
    backslashes before passing it to compgen.

In these cases, since readline did not detect a quote character in the original
word to be completed, bash-4.3 

Patch (apply with `patch -p0'):

*** ../bash-4.3/externs.h       2014-01-02 14:58:20.000000000 -0500
--- externs.h   2014-03-13 14:42:57.000000000 -0400
***************
*** 325,328 ****
--- 325,329 ----
  extern char *sh_backslash_quote_for_double_quotes __P((char *));
  extern int sh_contains_shell_metas __P((char *));
+ extern int sh_contains_quotes __P((char *));
  
  /* declarations for functions defined in lib/sh/spell.c */
*** ../bash-4.3/lib/sh/shquote.c        2013-03-31 21:53:32.000000000 -0400
--- lib/sh/shquote.c    2014-03-13 14:42:57.000000000 -0400
***************
*** 312,313 ****
--- 312,327 ----
    return (0);
  }
+ 
+ int
+ sh_contains_quotes (string)
+      char *string;
+ {
+   char *s;
+ 
+   for (s = string; s && *s; s++)
+     {
+       if (*s == '\'' || *s == '"' || *s == '\\')
+       return 1;
+     }
+   return 0;
+ }
*** ../bash-4.3/pcomplete.c     2013-08-26 15:23:45.000000000 -0400
--- pcomplete.c 2014-03-25 17:23:23.000000000 -0400
***************
*** 184,187 ****
--- 184,188 ----
  COMPSPEC *pcomp_curcs;
  const char *pcomp_curcmd;
+ const char *pcomp_curtxt;
  
  #ifdef DEBUG
***************
*** 754,757 ****
--- 755,784 ----
          dfn = (*rl_filename_dequoting_function) ((char *)text, 
rl_completion_quote_character);
        }
+       /* Intended to solve a mismatched assumption by bash-completion.  If
+        the text to be completed is empty, but bash-completion turns it into
+        a quoted string ('') assuming that this code will dequote it before
+        calling readline, do the dequoting. */
+       else if (iscompgen && iscompleting &&
+              pcomp_curtxt && *pcomp_curtxt == 0 &&
+              text && (*text == '\'' || *text == '"') && text[1] == text[0] && 
text[2] == 0 && 
+              rl_filename_dequoting_function)
+       dfn = (*rl_filename_dequoting_function) ((char *)text, 
rl_completion_quote_character);
+       /* Another mismatched assumption by bash-completion.  If compgen is 
being
+                run as part of bash-completion, and the argument to compgen is 
not
+                the same as the word originally passed to the programmable 
completion
+                code, dequote the argument if it has quote characters.  It's an
+                attempt to detect when bash-completion is quoting its filename
+                argument before calling compgen. */
+       /* We could check whether gen_shell_function_matches is in the call
+        stack by checking whether the gen-shell-function-matches tag is in
+        the unwind-protect stack, but there's no function to do that yet.
+        We could simply check whether we're executing in a function by
+        checking variable_context, and may end up doing that. */
+       else if (iscompgen && iscompleting && rl_filename_dequoting_function &&
+              pcomp_curtxt && text &&
+              STREQ (pcomp_curtxt, text) == 0 &&
+              variable_context &&
+              sh_contains_quotes (text))       /* guess */
+       dfn = (*rl_filename_dequoting_function) ((char *)text, 
rl_completion_quote_character);
        else
        dfn = savestring (text);
***************
*** 1523,1527 ****
  {
    COMPSPEC *cs, *oldcs;
!   const char *oldcmd;
    STRINGLIST *ret;
  
--- 1550,1554 ----
  {
    COMPSPEC *cs, *oldcs;
!   const char *oldcmd, *oldtxt;
    STRINGLIST *ret;
  
***************
*** 1546,1552 ****
--- 1573,1581 ----
    oldcs = pcomp_curcs;
    oldcmd = pcomp_curcmd;
+   oldtxt = pcomp_curtxt;
  
    pcomp_curcs = cs;
    pcomp_curcmd = cmd;
+   pcomp_curtxt = word;
  
    ret = gen_compspec_completions (cs, cmd, word, start, end, foundp);
***************
*** 1554,1557 ****
--- 1583,1587 ----
    pcomp_curcs = oldcs;
    pcomp_curcmd = oldcmd;
+   pcomp_curtxt = oldtxt;
  
    /* We need to conditionally handle setting *retryp here */
*** ../bash-4.3/patchlevel.h    2012-12-29 10:47:57.000000000 -0500
--- patchlevel.h        2014-03-20 20:01:28.000000000 -0400
***************
*** 26,30 ****
     looks for to find the patch level (for the sccs version string). */
  
! #define PATCHLEVEL 9
  
  #endif /* _PATCHLEVEL_H_ */
--- 26,30 ----
     looks for to find the patch level (for the sccs version string). */
  
! #define PATCHLEVEL 10
  
  #endif /* _PATCHLEVEL_H_ */

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/